I just finished reading the section of the qiskit textbook on quantum error correction using repetition codes(https://qiskit.org/textbook/ch-quantum-hardware/error-correction-repetition-code.html) and based on the experiments they ran, I’m only seeing repetition codes being used to encode logical bits (i.e. qubits in their independent $|0\rangle$ or $|1\rangle$ basis states).
I thought the whole purpose of developing the syndrome measurement technique was to prevent the breakdown of qubits in superposition. But then the experiments just went on to use it for encoding qubits that are not in superposition (logical bits) instead.
Was this done solely for simplicity or does the RepetitionCode object currently not allow us to do experiments on qubits in superposition?